从java代码执行CURL命令答案

【问题标题】：Execute CURL command from java code从java代码执行CURL命令
【发布时间】：2017-08-08 15:17:21
【问题描述】：

我想从 java 代码中执行 curl 命令。我已经看过几个文档，关于相同的stackoverflow问题。但它没有给出想要的结果，我正在尝试运行这个 curl 命令：

curl --noproxy <ip> 
-i 
-d "INSERT IN GRAPH <http://graph.com>{ <prop/Advanced_Data_Types> rdf:type owl:NamedIndividual ,
                                    <http://abcd/Video> ,
                                   <http://abcd/LearningResource/BookChapter> ;
                           <http://abcd/hasAuthor> <prop/Eric_Grimson> ;
                           <http://abcd/inLanguage> <http://abcd/#Hindi> ;
                           <http://abcd/sourceOrganization> <prop/IIT_Hyderabad> .}" 
-u "demo:demo" 
-H "Content-Type: application/sparql-query" http://<ip>:<port>/DAV/home/dba/xx

还有JAVA代码：

ProcessBuilder pb = new ProcessBuilder(
            "curl",
            "-i",
            "-d \"INSERT IN GRAPH <http://graph.com>{ <prop/Advanced_Data_Types> rdf:type owl:NamedIndividual ,<http://abcd/Video> ,<http://abcd/LearningResource/BookChapter> ;<http://abcd/hasAuthor> <prop/Eric_Grimson> ;<http://abcd/inLanguage> <http://abcd/#Hindi> ;<http://abcd/sourceOrganization> <prop/IIT_Hyderabad> .} ",
            "-u \"demo:demo\"",
            "-H \"Content-Type: application/sparql-query\"",
            "http://<ip>:<port>/DAV/home/dba/xx");

    pb.redirectErrorStream(true);
    Process p = pb.start();
    InputStream is = p.getInputStream();

    String line;
    BufferedInputStream bis = new BufferedInputStream(is);
    System.out.println(bis);

我的代码有什么问题吗？我想使用这个特殊的 curl 命令。请帮忙。

【问题讨论】：

命令行中的空格表示新参数。
谢谢。它有效。

标签： java curl

【解决方案1】：

您对如何将命令行转换为字符串参数列表的理解有些不正确。（这大致相当于 Unix shell 的工作方式）。

通常，当命令行中出现空格时，它意味着开始一个新参数。所以

"-H \"Content-Type: application/sparql-query\""

应该是

"-H", "\"Content-Type: application/sparql-query\""

【讨论】：

【解决方案2】：

我就是这样在java中执行curl的。

    public static String invokeCurlGet(String _host, int _connectTimeout, int _maxTimeout, int _maxResLength, Charset _charset) throws IOException
    {
        byte[] res = execute("curl --connect-timeout " + _connectTimeout + " --max-time " + _maxTimeout + " -X GET " + _host, _maxResLength);

        return new String(res, _charset);
    }

    public static byte[] execute(String _cmd, int _maxResLength) throws IOException
    {
        Process process = Runtime.getRuntime().exec(_cmd);

        try
        {
            int result = process.waitFor();
            if(result != 0)
            {
                throw new IOException("Fail to execute cammand. Exit Value[" + result + "], cmd => " + _cmd);
            }
        }
        catch(InterruptedException e)
        {
            process.destroyForcibly();

            throw new IOException(e);
        }

        BufferedInputStream in = null;

        try
        {
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            in = new BufferedInputStream(process.getInputStream());
            byte[] buf = new byte[1024];
            int read = 0;

            while((read = in.read(buf)) != -1)
            {
                out.write(buf, 0, read);
                out.flush();

                if(_maxResLength > 0 && out.size() > _maxResLength)
                {
                    throw new IOException("Response length exceeded.");
                }
            }

            return out.toByteArray();
        }
        finally
        {
            if(in != null)
            {
                in.close();
            }
        }
    }

    public static void main(String[] args) throws Exception
    {
        System.out.println(invokeCurlGet("http://127.0.0.1:9000?messageId=aaaaaaaa&to=asdfsefwaf", 3, 10, 0, Charset.defaultCharset()));
//      System.out.println(invokeCurlGet("https://github.com", 1, 1, 0, Charset.defaultCharset()));
    }

【讨论】：